Isso foi abordado no Ask Ubuntu algumas vezes, aqui está um post com algumas capturas de tela que pode ser útil :
- Press Alt-F2 and enter
gconf-editor
.- Navigate to apps/nautilus/desktop.
- Deselect volumes_visible.
If you want your other volumes to be visible, you will have to add them manually:
- Right click on desktop and click 'Create Launcher...'
- Change the type to 'Location'
- Change the name to suit you.
- Browse for the volume.
- Change the icon to the 'block device' icon at
/usr/share/icons/YOUR_THEME/devices/48/block-device.svg
Click OK.